Imaging

What is meant by imaging?

The field of imaging can involve any type of technology that generates, collects and visualises images. Micro Control Instruments offers a range of solutions for preclinical and translational research. Our equipment is focused on the microscopy field, allowing to view and image elements too small to be visible with the human eye.

What samples are your imaging equipment designed for?

Scientific research is conducted on a great variety of models. In biology, the samples are usually classified within the following categories: in vitro, ex vivo and in vivo. In vitro studies are experiments performed outside of a living animal, such as cell cultures. This category often includes the ex vivo studies, which are experiments performed on tissue from an organism in an external environment with minimal alteration of its biological conditions. An example of ex vivo studies are brain slices for electrophysiology recordings. Finally, in vivo studies encompass experiments conducted on a whole living organism.

Studies of fundamental biological processes, such as cellular function and molecular processes

Intravital studies

Visual representation of Physiological functions

Stem cell research

Studies of vasculature, particularly cardiovascular function

Developmental research

What is in vivo imaging?

In vivo imaging entails microscopic imaging of any cells, mechanisms or processes in real-time within a living organism. These applications are performed in awake or anesthetised head-fixed animals or in freely moving animals. The methods used for this approach are designed to be minimally or non-invasive. The implants we recommend are carefully considered to not cause any inflammation or scar tissue that could impact negatively on the health of the animals and data collected.

How is in vivo different to in vitro imaging?

In vitro imaging includes microscopy studies of live cells, biological molecules or microorganisms outside of their normal biological environment. This is usually performed in culture or tissue slices. This differs to the in vivo imaging approach where imaging is done on specific reactions to chemicals or different processes within a living organism.

What is ex vivo imaging?

Ex vivo research is similar to in vitro in the sense that imaging is done on cell cultures or tissue slices. However, with ex vivo experiments great consideration should be taken to ensure that the environment that the samples are imaged in is equivalent to that in which it was inside the living organism, such as the temperature, the chemical composition and pH. With in vitro imaging, one can usually only apply the results to the specific cell line studied, whereas with ex vivo imaging the data is only applicable to the specific organism, under the particular conditions, from which the sample(s) were taken.

What type of microscope do I need for imaging research?

The type of microscope you need would depend on your experimental design. For in vitro imaging you might need a more complex range of substage optics, contrast and/or light filtering components. In vivo microscopes, such as our In Vivo CleverScope, are especially ideal when space is required around the scope and a simple light source would suffice for imaging in larger animals. In vivo microscopes can also be beneficial if transmitted light is not suited to your sample.

Do you offer a microscope compatible for in vivo imaging of larger animals?

Yes, our In Vivo CleverScope is a motorised microscope with removed substage optics. This creates the ideal space for fixation of larger animals nearer to the microscope for focus on your in vivo imaging area.

What is essential for in vivo imaging?

In vivo imaging is often also referred to as fluorescence animal imaging. Therefore, fluorescent proteins or reporters should be administered to the animals. Alternatively, specific genetically modified animal lines express fluorescent markers. This makes the differentiation and imaging of the specific cells or processes studied possible under a microscope. The type of cells you want to study will further impact on the dye or fluorescent protein chosen. The green fluorescent protein (GFP) is the most popular reporter of expression, thanks to its low phototoxicity and ease of use. Alternatively, a lot of fluorophores at the near-infrared (NIR) are being developed and are preferred to attenuate cell damage from photobleaching and phototoxicity.

What type of setup is required for imaging?

Here are some things to consider when you are planning an imaging rig:

Fluorophores – For the detection and mapping of specific fluorescent markers, one needs to inject or transfect the specific cells or tissues to be studied with fluorophores. These fluorescent compounds can re-emit light upon excitation, making it possible for one to view the cells or processes they are involved in, under a microscope.

Genetically encoded calcium indicators (GECI) – cells should be transfected/injected with GECI where after imaging can be done with a fluorescence microscope and a scientific camera. With calcium influx as with action potentials, the GECI makes it possible to image activity in specific neurons.

Stereotaxic frames or Head-fixation devices – Depending on your experimental design you would need to anesthetise and use a head-fixation device or stereotaxic frame to bring your animal near the microscope (in vivo imaging). For behavioural imaging research, these components would be replaced by implant devices, such as the OASIS Implant system by Mightex Systems.

Sample-holding Mount – For in vitro imaging you might opt in for a separate sample-holding mount with adjustable height, such as our high-quality but cost-effective EasyAdjust-In Vitro. This manual mounting pillar offers all the flexibility you need to precisely place your sample.

Microscopes – the type and specific optics required will depend largely on your research questions and animal(s) studied. Larger animals could be imaged with a simple reflected light microscope whilst small animals such as drosophila should be imaged with microscopes that include a transmitted light pathway and a complete set of optics. The MCI CleverScope was cleverly designed to be compatible with most leading brands of optics, such as Leica, Nikon, Olympus, etc.

Contrast techniques – Some of the most used contrast methods for effective imaging of a specimen, are DIC (Differential Interference Contrast), DGC (Dodt Gradient Contrast), Phase contrast, and Oblique contrast. If you need further information on how these options would be used, please get in touch.

Illumination – For viewing your specimen under the microscope you would require illumination. The type of light source to use, will depend on the fluorophores and/or contrasting technique used as well as the specific cell types or tissue studied. Light source options include bright-field illumination and epifluorescence illumination. A variety of different wavelength and power output LEDs are available on the market to provide the perfect illumination for your experiments. Mightex Systems also designed a great spatial illuminator that could benefit your research. Read more on this superb product here.

Filters – To provide you with more flexibility in your research and offer you different options for future experimental paradigms, there are a variety of filter sets that can be integrated into your imaging microscope. Every filter set available on the market has been developed for enhancing specific fluorophores/GECI in your specimen. Generally, filter sets include three components named an excitation filter (selects excitation wavelength from light source), dichroic mirror (passes specific wavelength whilst reflecting others), and an emission filter. With regards to the emission filter, either a longpass or bandpass filter may be required, depending on whether you do not require spectral differentiation or a better signal-to-noise ratio, respectively. Further options are available as single-band or multi-band filter sets. The former is the best for high-contrast and low bleed through images, whilst the latter was specifically developed for high-speed multi-colour imaging.

Cameras – For cameras there are options of CCD (charge-coupled devices) or CMOS (complementary metal-oxide semiconductor) sensors. CCD cameras are more sensitive to light and can produce high-quality and low noise images, but they are much more expensive than CMOS cameras. CMOS cameras, on the other hand, require more light to create similar quality images than that of CCD cameras.

Do you offer any deep-tissue imaging components?

Yes, our DiveScope, the smallest complete epifluorescence deep-tissue multi-channel imaging system is available to order now and includes user-friendly software. We offer different models for the DiveScope, to meet your requirements for smaller (200µm) and larger (500µm) fields of view.

Alternatively, the Pryeris an endoscopic objective that will fit on any type of microscope and will allow you to image deep tissue in vivo.